Chrome and Firefox both update roughly every six weeks give or take a few days.  Chrome 27 (current release) is the last major release using the Webkit rendering Engine, as of Chrome 28 they will be using Blink (a fork of Webkit).

IE uses the Trident rendering engine, and both clients use a different set of HTML standards.  Because of this, you are seeing differences in performance and layout.  That's not the fault of the clients per se, as some of these standards are still in flux.  However proper web development includes heavy cross client testing, and that simply was not done prior to the revamp.

While XP users are limited to IE 8, it is important to release that Windows XP ends support entirely in 2014.   XP users would get a much better web experience using a more up to date client like Chrome or Firefox, however those same people should seriously be considering a OS upgrade in the near future as well.

Lastly, To access the download folder in Chrome, press CTRL+J.